Figure 4. IKKα deletion ameliorates respiratory epithelial oncogenicity of mutant KRAS^G12D.

Conditional IKKα (Chukf/f) or IKKβ (Ikbkbf/f) gene-deleted mice were intercrossed with mice carrying a loxP-STOP-loxP.KRAS^G12D conditional allele (LSL.KRAS^G12D; all C57BL/6) and their offspring received 5 x 10⁸ PFU intratracheal Ad- Cre and was killed four months later. (A) Schematic of experimental time-course (boxes= months) and topology of IKK-deleted (pink cytosol) versus KRAS^G12D-mutant (red nucleus) cells in this model, where IKK-deletion and oncogenic KRAS^G12D expression uniquely coincide in the same cells. (B) Frequency distribution of lung tumorigenesis with n and χ² P values. ns, *, **, and ***: P > 0.05, P < 0.05, P < 0.01, and P < 0.001, respectively, for the indicated comparisons by Fischer’s exact test. (C, D) Data summary of relative lung tumor fraction and total lung tumor volume (burden) per lung with raw data points (dots), Tukey’s whiskers (boxes: interquartile range; bars: 50% extreme quartiles), and Kruskal-Wallis ANOVA P values. ns, *, **, and ***: P > 0.05, P < 0.05, P < 0.01, and P < 0.001, respectively, for the indicated comparisons by Dunn’s post-tests. (E) Representative hematoxylin and eosin-stained lung tissue sections. Arrows denote lung tumors.